Left 4 Dead 2!

Rock and stone!

(Deep Rock galactic) The most fun coop fps in my opinion

Halo is the all time best co-op shooter hands down. The lore is surprisingly deep and the story telling is top notch.

Of course I am referring to 1, 2, 3, odst, and reach.

3 and on support 4 player co-op. All are in the master chief collection. Added bonus that odst is like an unofficial firefly reunion

Left 4 Dead 1 & 2

Killing Floor

Deep Rock Galactic

If your into realistic FPS games then you want to go with bodycam, 6 days or if you want a solid mix between realistic and not so realistic then Insurgency Sandstorm is good.

But if you want good lore then start with doom and work your way up the series.

I have mixed feelings about Doom 1993 and Doom 2. Used to play that with my brother, which was great. But eventually he’d start killing me instead of demons until I cried, which was bad.

Still great games.

Third person, not first: It Takes Two is adorable. The developers, Hazelight Studios, also made A Way Out. They specialise in co-op and they’re working on a new game, Split Fiction. It Takes Two, as of May 29th, is DRM-free on Steam and Steam Deck, and hopefully the new one will follow